Change parent pom to 4.2.1.CR1-SNAPSHOT
Update integration tests repo url to 4.2.luna

The integrations tests repo url in root pom.xml of 4.2.x branch
pointed to master - it needs to point to 4.2.luna. I created
the corresponding jenkins job which publishes the correct p2 repo.
And now I'm changing the url in the pom.xml to reflect that.